Vacuum cleaner

ABSTRACT

The invention provides a vacuum cleaner (10) having a housing (12) containing an apparatus (22) for separating dirt and dust from an airflow. The vacuum cleaner is configured so as to allow the cleaner to be positioned on a flight of stairs. The forward end (32) of the housing is shaped so as to facilitate the sliding of the vacuum cleaner over the flight of stairs in an upward direction.

CROSS-REFERENCES TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

REFERENCE TO A "MICROFICHE APPENDIX"

Not Applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a vacuum cleaner, particularly to acylinder-type vacuum cleaner.

2. Description of the Related Art

Very few vacuum cleaners, upright or cylinder, are designed to be stablypositioned on a flight of stairs. UK patent No. 658328 discloses acylinder-type machine having skids attached to the underside of thecylindrical housing, the skids having notches located therein so thatthe machine can be "hooked" onto a stair nosing. This allows the useruse of both hands to operate the hose or wand of the cleaner. A similarbut improved design is described in our pending UK patent applicationNo. 2292881A and corresponding PCT application No. WO 96/07350. Analternative design is illustrated in DE-U-9302645.

None of these prior art machines is designed or intended to be moved upor down a flight of stairs other than by the user lifting the entiremachine and repositioning it on another convenient part of the flight ofstairs. This can be quite cumbersome, especially if the user must alsokeep hold of the hose or wand during repositioning of the machine. Itwould be more convenient if the machine could be dragged or slid up theflight without having to physically lift the body of the machine but theconfiguration of each prior art machine is such that dragging or slidingis difficult and awkward and results in a substantial jolting of themachine. This can be detrimental to the operation of the machine.

U.S. Pat. No. 3,015,123 illustrates a vacuum cleaner which is intendedto be slid or pulled up a flight of stairs, but the stability of themachine is insufficient for safe use.

SUMMARY OF THE INVENTION

An object of the invention is to provide a vacuum cleaner which can beeasily manoeuvred on a flight of stairs.

The invention provides a vacuum cleaner as set out in claim 1.Advantageous features of the invention are set out in the subsidiaryclaims.

The shaping of the forward end of the housing to include an upwardlyinclined nose adapted to present a smooth, inclined surface to a stairnosing so as to facilitate sliding of the machine up a flight of stairsmeans that upward sliding of the machine is smoother and less jolting sothat the likelihood of damaging the machine by such action is minimised.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described with reference to theaccompanying drawings, wherein:

FIG. 1 is a side sectional view of a vacuum cleaner according to theinvention positioned on a flight of stairs; and

FIGS. 2a-2d illustrate progressive positions of the vacuum cleaner whencaused to slide upon a flight of stairs in the upward direction.

FIG. 3a and 3b shows an alternative embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

A vacuum cleaner according to the present invention is illustrated inFIG. 1. The vacuum cleaner 10 consists essentially of a housing 12having a base 14 and a cover 16. A hose 18 is connected to the cover 16of the housing 12 by means of a swivel coupling 20. Positioned insidethe housing 12 are dust separating apparatus 22, a motor 24 andconnection means for causing the vacuum cleaner to operate so as to drawdirty air into the housing 12 along the hose 18, to separate dirt anddust particles from the air flow, and to expel clean air to theatmosphere. The interior workings of the machine 10 do not form anessential part of the present invention and will not be described anyfurther here.

The base 14 of the cover 12 incorporates a recess 26 which canaccommodate the nosing of a stair tread. By means of this shaping, whichforms the subject of our pending UK patent application No. 2292881A andPCT application No. WO 96/07350, the machine 10 can be positioned on aflight of stairs in a stable manner. The base 14 of the cover 12 restson adjacent stair treads A, B at contact portions 28a, 28b.

When the machine 10 is in use, there is a desire on the part of the userto drag the machine 10 up the flight of stairs merely by pulling on thehose 18. In order to facilitate the sliding of the machine 10 up thestairs in the direction of the arrow 30, a nose or shaping 32 isprovided on the forward end of the housing 12. The nose 32 projectsforwardly of the casing 12 and is inclined upwardly with respect to thegeneral plane of the base 14 of the cover 12 such that, when the userapplies a pulling force to the hose 18 in the direction of arrow 30, thenose 32 presents a smooth surface to the nosing of the stair Cimmediately above the uppermost stair B on which the machine iscurrently resting. Sufficient pulling force in the direction of arrow 30will cause the machine 10 to be pulled upwardly over the flight ofstairs and the nosing 32 facilitates the smooth upward passage of themachine 10 by virtue of its shaping. The lower surface 34 of the nose 32provides a surface by means of which the forward portion of the machine10 is guided smoothly over the nosing of stair C.

FIGS. 2a-2d illustrate the upward motion of the machine 10 when anupward force is applied to the hose 18 in the direction of the arrow 30.The position illustrated in FIG. 1 is again illustrated in FIG. 2a andwill now be regarded as a starting position. Contact portions 28a and28b are in contact with the treads of stairs A and B. The foremostextremity of nose 32 is in contact with or adjacent the nosing of stairC.

Application of a pulling force in the direction of the arrow 30 causesthe machine 10 to ride upwardly over the stairs. Contact portions 28aand 28b move out of contact with the treads of stairs A and B and themachine is then supported on the nosings of stairs B and C by contactwith the surface of the recess 26 (or another portion of the base 14 ofthe housing 12) and with the lower surface 34 of the nose 32respectively. Continued pulling in the direction of the arrow 30 causesthe machine 10 to ride further up on the nosings of stairs B and C untilthe machine is supported by contact with the base 14 of the housing 12on either side of the recess 26. Eventually, the nosing of stair C willcome into contact with at least one wall of the recess 26 whereupon thecontact portions 28a, 28b will be brought into contact with the treadsof stairs B and C. Further movement in the direction of arrow 30 willensure that the contact portions 28a, 28b are positioned sufficientlyfar from the nosings of stairs B and C for the machine 10 to be stablysupported. The new stable position is identical to that shown in FIG. 2abut with the machine 10 resting on stairs B and C instead of stairs Aand B.

The embodiment illustrated in the accompanying drawings shows that thehousing 12,12' incorporates cyclonic means for separating dirt and dustfrom the air flow drawn in through the hose 18,18'. This is a preferablyfeature but should not be regarded as limiting to the present invention.

I claim:
 1. A vacuum cleaner comprising a housing containing anapparatus for separating dirt and dust from an airflow, a base of thehousing incorporating an upwardly extending recess for accommodating astair nosing, and contact portions arranged on either side of the recessfor contacting two adjacent stair treads of a flight of stairs andsupporting the vacuum cleaner thereon, the forward end of the housinghaving an upwardly inclined nose with a smooth, inclined lower surfacewherein when the vacuum cleaner is supported on the two adjacent stairtreads, the smooth lower surface extends towards an upper stair nosingimmediately above the stair nosing accommodated by the recess and isinclined to the vertical so that the smooth, lower surface facilitatessliding of the vacuum cleaner in an upward direction over the flight ofstairs.
 2. A vacuum cleaner as claimed in claim 1, wherein the smooth,inclined lower surface is substantially planar.
 3. A vacuum cleaner asclaimed in claim 2, wherein the upwardly extending recess has a rearwardinclined surface which is substantially parallel to the smooth, planarlower surface of the upwardly inclined nose.
 4. A vacuum cleaner asclaimed in any one of claims 1, 2 or 3, wherein the apparatus forseparating dirt and dust from the airflow is cyclonic.